The present invention relates generally to a method for analyzing an electrical utility power system, and more particularly to a method for using fuzzy logic to identify and classify power system events.
Generally, electrical power originates at a generation station and is transmitted to a load by a system of conductors and other equipment that make up an electrical power system. The equipment that makes up an electrical power system can include switches, reclosers, insulators, capacitors, transformers, and the like. Over time, or as the result of some particular cause such as contact of a conductor by vegetation, the conductors and equipment can cease to operate normally or fail. Sometimes a failure of conductors or equipment results in an abnormally high current that can further damage the distribution system or injure end users or damage end users' devices and equipment.
In an effort to identify failed devices quickly, utilities may monitor the operation of an electrical power system by monitoring a signal indicative of a property such as current. However, conventional methods of monitoring properties of an electrical power system generally require human experts to analyze data obtained from the power system. In this regard, experts may not be available for analysis when needed and can be very expensive. Furthermore, automated analytical systems using only classical (crisp) logic may not work well when presented with data containing uncertainties introduced by missing data and inaccurate measurements or may not sufficiently encode the human knowledge needed to analyze data. Thus, this invention provides a method for automatically identifying and characterizing power system events in a reliable and efficient manner without overwhelming the user with data. This is important for safe, reliable, and economical operation of the electric power system. It allows efficient determination of what caused the events observed on a power system. This invention allows system operators or others to better assess the health of the system, take corrective actions, and restore service to customers, while minimizing adverse effects to the system itself or to personnel.